Developer website: AppleBit Technologies
With DVD RegionCode Unlock a non-administrative user is given access to set the DVD region code the first time they insert a DVD.
Use this simple install on the computer(s) to allow a user to set the region code once (without requiring an administrator password).
This will not allow them to set it once; after the region code is set once, it will again require an administrator password, thus preventing all 5 regions from being used up. Simple as that.